Subtract 3/7 from 20/72
20/72 - 3/7 is -19/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Likewise, for the 2nd fraction, since 7 × 72 = 504,
3/7 = 3 × 72/7 × 72 = 216/504 - Subtract the two like fractions:
140/504 - 216/504 = 140 - 216/504 = -76/504 - After reducing the fraction, the answer is -19/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/72-3/7 20/72-6/7 20/72-3/14 60/72-3/7 20/72-9/7 20/72-3/21 20/72-15/7 20/72-3/35 20/72-21/7 20/72-3/49